WO2014132986A1 - Cultivation method, seedling raising method, ultrasonic disease control device, disease control method, production method and plant body or seedling - Google Patents

Abstract

Provided is a technique which, by irradiating plants under cultivation with ultrasonic waves, induces disease resistance in the plants to produce plant bodies or seedlings that control or are resistant to disease. The tomato wilt disease suppression effect of ultrasonic treatment over the growing period (cultivation period) was examined. In the tests, tomatoes were sequentially seeded, nursed, inoculated, and grown in pots filled with sterilized soil, and were continually irradiated with ultrasonic waves during this process. As a result, the wilt disease suppression effect of ultrasonic treatment was seen over the growth period. For example, as shown in the result of example 1, a large suppression effect of the incidence of disease was observed, with 0.54 in the ultrasonic treatment area compared to 1.61 for non-treated area. Further, in the VMA combined use area had an incidence of disease of 0.27, confirming an increase in the disease suppression effect.

Description

Cultivation method, seedling method, ultrasonic disease control device, disease control method, production method and plant body or seedling

The present invention relates to a plant cultivation method, a seedling method, an ultrasonic disease control apparatus, a disease control method, a production method, and a plant body or a seedling for inducing disease resistance against pathogens such as filamentous fungi, for example.

 Reducing food production due to plant diseases is expected to reach more than 15% of the ideal yield. At present, a pesticide (bactericide) having a bactericidal action against chemical substances, particularly pathogens, is generally used for controlling plant diseases. However, the establishment of disease control technology that does not rely on chemical pesticides is socially demanded due to the emergence of resistant bacteria, residue in food, and environmental effects.

In recent years, there has been an increasing interest in environmental conservation in agricultural production sites, and an increasing number of producers are engaged in cultivation techniques that reduce the use of agricultural chemicals and chemical fertilizers as much as possible in order to reduce the burden on the environment. In addition, the Law on Promotion of Organic Farming has been enforced, and research and development related to production technologies aimed at reducing environmental impacts are being promoted by universities and public testing institutions, and the development of new control technologies that do not depend on chemical pesticides is desired.

Various types of technologies have been proposed. For example, in a lighting device for controlling plant pests, spore formation and fungal growth of fungi such as gray mold disease and powdery mildew are reliably suppressed, and disease resistance is surely induced in plants, causing disease generation and plant growth. There is a method for reducing the damage, suppressing the influence on plant flower bud formation, etc., and efficiently controlling nocturnal pests (see, for example, Patent Document 1). Similarly, as a technology using light, the plant disease control lighting device has a simple configuration that does not require adjustment of light output, and prevents plant burn resistance caused by ultraviolet irradiation, while preventing plant burn damage. A method has been proposed in which the amount of ultraviolet irradiation necessary to induce the disease is secured and plant diseases are suppressed (see Patent Document 2).

JP 2009-153397 A JP 2012-61 A

By the way, as described in Patent Documents 1 and 2 described above, many resistance induction and disease control methods using light have been proposed, and research, verification tests, and the like have been conducted with the aim of spreading to production sites. However, when light is used, there is a plant in which resistance is induced and a plant in which resistance is not induced depending on the type of wavelength (color type), and there is a problem that the reaction varies greatly depending on the type of plant. Moreover, the leaf color of the plant may be affected depending on the type of light, and there are problems such as limited available crops. In addition, although technology related to resistance induction using wind has been proposed, it has not been sufficiently verified whether resistance is actually induced, and the disease prevention effect due to wind has not been clarified. Also, even at production sites, control technology using this technology is not widespread, and another technology has been demanded.

Many disease control methods based on resistance induction using chemical substances (plant activators) and microorganisms have been invented, and many techniques are widely used in production sites. However, when these are used at the production site, procedures such as registration of agricultural chemicals have to be taken, and a large amount of money is required. Therefore, there are few technologies that have been put to practical use. In addition, when a chemical substance that is not a natural product is registered as an agrochemical, there is a problem that it is difficult to use it at production sites such as organic agriculture. From this viewpoint, an alternative or complementary technique has been demanded.

The present invention has been made in view of the above situation, and is to provide a technique for solving the above-described problems.

The cultivation method according to the present invention irradiates a plant to be cultivated with ultrasonic waves.
Further, the period of irradiation with the ultrasonic waves may be a growth period.
Moreover, the period for irradiating the ultrasonic wave may be a seedling raising period.
Moreover, you may perform the process by a plant activator with respect to the plant of the said cultivation object with the said ultrasonic irradiation.
The seedling raising method which concerns on this invention irradiates an ultrasonic wave with respect to a seedling plant in the seedling raising period before planting to this field.
The ultrasonic disease control apparatus of the present invention irradiates ultrasonic waves to a plant to be cultivated.
Further, ultrasonic waves having a predetermined frequency may be alternately generated at long pulse intervals and short pulse intervals.
The disease control method of the present invention controls plant diseases using the above cultivation method, seedling raising method or ultrasonic disease control apparatus.
The production method of the present invention produces a plant or seedling that is resistant to disease using the cultivation method, seedling raising method or ultrasonic disease control apparatus.
The seedlings of the present invention are irradiated with ultrasonic waves during the seedling raising period before being planted in the main field.
The ultrasonic wave may be generated by alternately generating a predetermined frequency at a long pulse interval and a short pulse interval.

According to the present invention, by irradiating the plant to be cultivated with ultrasonic waves, it is possible to control diseases that occur at other times, to control diseases that are infected at other times, In addition, it is possible to provide a technique capable of producing a plant body or a seedling that is resistant to pathogens that are infected or diseased at other times.

It is a table which shows the verification result (Examples 1 and 2) of the tomato wilt disease onset suppression effect by the ultrasonic treatment through the growth period based on 1st Embodiment. It is a table which shows the verification result (Example 3, 4) of the tomato wilt disease onset suppression effect by the ultrasonic treatment at the time of seedling raising based on 1st Embodiment. It is a table which shows the verification result (Example 5) of the influence on the tomato wilt disease onset suppression effect by the ultrasonic treatment period at the time of seedling raising based on 1st Embodiment. It is a table which shows the verification result (Example 6) of the influence on the tomato wilt disease onset suppression effect by the ultrasonic treatment period at the time of seedling raising based on 1st Embodiment. It is a figure which shows the ultrasonic disease control apparatus and output pattern of an ultrasonic wave based on 1st Embodiment. 10 is a table showing verification results (Examples 7 to 9) of rice blast control effect by ultrasonic treatment during seedling raising according to a second embodiment. It is a table which shows the verification result of the rice blast prevention | control effect by 40-kHz ultrasonic irradiation based on 3rd Embodiment. It is a table which shows the verification result of the cabbage dwarf prevention effect by 40kHz ultrasonic irradiation based on 4th Embodiment. It is a table. It is a table which shows the verification result of the blast disease control effect at the time of using two types of ultrasonic waves of 21 kHz and 40 kHz based on 5th Embodiment. It is a table. It is a table which shows the verification result of the tomato powdery mildew prevention effect at the time of using 3 types of ultrasonic waves based on 6th Embodiment, 21kHz, 28kHz, and 40kHz.

The present embodiment (hereinafter simply referred to as an embodiment) will be described with reference to the drawings.

<First Embodiment>
In the first embodiment, three types of test 1 to test 3 were conducted with respect to the tomato wilt disease control test. Details of Test 1 to Test 3 will be described later. In Test 1, the effect of ultrasonic irradiation during the cultivation period was confirmed. In Test 2, the effect of ultrasonic irradiation only during the seedling period was confirmed. The effect by the difference in the ultrasonic irradiation period was confirmed.

Ultrasonic exposure:
FIG. 5A shows the ultrasonic disease control apparatus 10 used in this test, and FIG. 5B shows a pulse output pattern. As shown in the figure, the ultrasonic disease control apparatus 10 used in this test includes an output amplifier device 30 of 100 W, a ceramic vibration element 20 that oscillates in resonance in the front-rear direction, and a control unit 40 that controls driving of the ceramic vibration element 20. With. The ultrasonic disease control apparatus 10 outputs an ultrasonic wave having a frequency of 40 kHz and outputs a pulse width (T1) of 5 milliseconds for 12 times with a long pulse interval (T2 = about 150 milliseconds) and a short pulse interval (T3 = about). 30 times) and 10 times output are generated alternately.

In the following tests, the section where this treatment was performed is referred to as “ultrasonic treatment section”, and the section where ultrasonic treatment is not performed is referred to as “no treatment section”. The ceramic type vibration element 20 was separated from the pot 50 where the plant was cultivated by 5 cm or more and exposed to ultrasonic waves at a distance of about 15 cm to 30 cm. The installation position of the ceramic type vibration element 20 is 15 cm to 30 cm in height and is located obliquely above the plant. The sound pressure of the ultrasonic waves is about 130 dB at the position of the irradiation target plant 30 cm from the ceramic type vibration element 20 and 120 dB or more at the position of 1 m. In addition, in order to confirm the effect of ultrasonic exposure in this test and subsequent tests, the ceramic type vibration element 20 having a strong directivity is used, but the present invention is not limited to this type. Similarly, this process does not limit the frequency of ultrasonic waves, the pulse interval, the sound pressure, and the installation position of the ceramic type vibration element 20.

Tomato wilt control test:
Tomato seeds (variety: Moneymaker) were cultivated for 16 hours under light irradiation conditions at 28 ° C. and for 8 hours under dark conditions at 25 ° C. for one week. Thereafter, ultrasonic treatment was continued in a greenhouse at a temperature of 20 to 30 ° C. for 2 weeks. Note that the variety of tomatoes is not limited to Moneymaker, and may be Momotaro, for example. Moreover, the pathogenic bacteria are not limited to the present bacteria.

Tomato wilt fungus (Fusarium oxysporum f. Sp. Lycopersici race 2 880621a-1 strain) was cultured with shaking in a potato dextrol liquid medium at 28 ° C. for 5 days. The spore concentration in the culture solution of tomato wilt fungus was diluted to 1 to 2 × 10 ⁷ spores / ml with distilled water and used as an inoculation source. Inoculation is partly by irrigation by rooting (inserting 3 tags with a width of about 1 cm in the soil at the time, partially cutting the tomato roots, and inoculating the inoculation source with 1 ml per tomato) Symptom evaluation was performed at 6 weeks, and the effect of sonication was tested by comparison with the untreated group.

The symptom evaluation of each tomato individual was performed by cutting the stem at the border and examining the severity of the disease from 0 to 4 based on the browning degree of the vascular part. The severity of the disease was evaluated in five stages as follows.
0: Healthy 1: Browning is observed in 25% of stems 2: Browning is observed in 26-50% of stems 3: Browning is observed in 51-75% of stems 4: Browning is observed in 76-100% of stems Is accepted,
The average disease severity was calculated using the following formula.
Average disease severity = (1 × A + 2 × B + 3 × C + 4 × D) / (4 × N)
(In the formula, A, the number of plants showing disease severity 1; B, the number of plants showing disease severity 2; C, the number of plants showing disease severity 3; D, the number of plants showing disease severity 4; N, Represents the total number of plants tested.)

1. Test 1
In Test 1, the tomato wilt disease suppression effect by ultrasonic treatment throughout the growing period (cultivation period) was verified. In this test, tomato was sown, seeded, inoculated and grown continuously in a pot filled with sterilized soil, and ultrasonic waves were continuously irradiated during that time. The results are shown in the table of FIG. 1 (Examples 1 and 2).

The test conditions are as follows. The tests of Examples 1 and 2 are both under the same conditions.
・ Ultrasonic waves continued to be irradiated throughout the cultivation period.
・ Tested 28 days after inoculation.
-The control value was calculated using the following formula.
Control value = (morbidity of untreated group−average disease degree of each treated group) × 100 / morbidity of untreated group. In VMA treatment, validamycin A having a purity of 99% (plant activator, Sumika Takeda Agricultural Chemical Co., Ltd.) was dissolved in water (VMA) so as to be 100 μg / ml and sprayed on the foliage using a spray. Other plant activators include validoxylamine A, probenazole, benzoisothiazole, thiazinyl, isothianyl.

As shown in the table of FIG. 1, as a result of the test 1, the effect of suppressing the onset of wilt disease by sonication throughout the growth period was observed. For example, as shown in the results of Example 1, the degree of illness was significantly suppressed as 0.54 in the ultrasonic treatment group compared to 1.61 in the non-treatment group.

Furthermore, in the VMA combined section, the disease severity was 0.27, and it was confirmed that the disease suppression effect by ultrasonic treatment was increased. A similar tendency was confirmed for Example 2.

2. Test 2
In test 2. Verification of the tomato wilt disease suppression effect by ultrasonic treatment during seedling raising was conducted. In this test, tomato seeds were sown in a cell tray filled with sterilized soil, cultivated for 1 week, and then irradiated with ultrasonic waves in a greenhouse at a temperature of 20 to 30 ° C. for 2 weeks. Then, it transplanted to the pot and inoculated the tomato wilt disease inoculation source one week later. The results are shown in the table of FIG. 2 (Examples 3 and 4). The tests of Examples 3 and 4 are both under the same conditions.

The test conditions are as follows:-Ultrasonic wave was continuously irradiated for 2 weeks during seedling raising.
・ Tested 28 days after inoculation.
-The control value was calculated using the following formula.
Control value = (morbidity of untreated area−average disease degree of each treated area) × 100 / morbidity of untreated area

As shown in the table of FIG. 2, as a result of the test 2, the ultrasonic treatment with a seedling period of 2 weeks showed an effect of suppressing the onset of wilt disease in this field. For example, in Example 3, the untreated disease severity is 1.73, whereas in the ultrasonic irradiation treatment section, the disease severity is 0.45, and a significant suppression effect is obtained. As described above, it was confirmed that the effect of suppressing the onset of wilt disease by ultrasonic treatment was persistent.

3. Test 3
In Test 3, the influence on the tomato wilt disease suppression effect by the ultrasonic treatment period at the time of raising seedlings was verified. Specifically, the disease-inhibiting effect was investigated for three types: a non-treated group, a one-week ultrasonic irradiation treatment group, and a two-week ultrasonic irradiation treatment group. In the 1 week ultrasonic irradiation treatment group, ultrasonic irradiation was performed in the latter half of the 2 weeks of seedling raising. The results are shown in the tables of Examples 3 and 4 (Examples 5 and 6). Note that the tests of Examples 5 and 6 are both under the same conditions.

The test conditions were as follows:-Ultrasound was continuously irradiated for 2 weeks or 1 week during seedling raising.
・ Tested 28 days after inoculation.
-The control value was calculated using the following formula.
Control value = (morbidity of untreated area−average disease degree of each treated area) × 100 / morbidity of untreated area

As shown in the tables of FIGS. 3 and 4, it was verified that the ultrasonic treatment during the seedling period had a sufficient disease-suppressing effect in this field even for one week, but the effect was higher in two weeks.

<Second Embodiment>
The second embodiment relates to a rice blast control test. Here, we verify the rice blast disease suppression effect by ultrasonic treatment during seedling raising. For ultrasonic exposure, as in the first embodiment, ultrasonic waves having a frequency of 40 kHz and a pulse width (T1) of 5 milliseconds are applied to a long pulse interval (T2 = about 150 milliseconds) and a short pulse interval (T3). = About 30 milliseconds) is used.

Rice (variety: Aichi Asahi) was sown in a 9 cm pot filled with sterilized soil and cultivated for 16 hours under 30 ° C. light irradiation conditions and for 8 hours under 25 ° C. dark conditions for 2 weeks. After continuing ultrasonic treatment for 2 weeks in a greenhouse at a temperature of 20 to 30 ° C., the plant height of rice was measured and spray inoculated with rice blast fungus (Magnaporthe oryzae P2) adjusted to 2 × 10 ⁴ spores / ml. After inoculation, the rice was transferred into an inoculation humidifier (Nippon Kaika Kikai Seisakusho Co., Ltd.) previously maintained at 27 ° C. and relative humidity of 100%. After moisturizing for 24 hours, the rice was transferred to a glass greenhouse. After cultivating for 16 hours under light irradiation conditions at 28 ° C, for 8 hours under dark conditions at 25 ° C for 1 week, the number of extension-type lesions formed on the third to third leaves was counted. It was. The results are shown in the table of Examples 6 (Examples 7 to 9). The tests in Examples 7 to 9 are all under the same conditions. The pathogenic bacterium is not limited to this bacterium, and the variety is not limited to Aichi Asahi.

The control value was calculated using the following formula.
Control value = (Disease level of untreated area−Average severity of treated area) × 100 / Disease degree of untreated area

Sonication for 2 weeks during the seedling period showed a subsequent blast disease suppression effect. For example, as shown in Example 7, the average disease severity is 7.89 in the untreated section, whereas the average disease severity is reduced to 5.00 in the treated section. As described above, it was confirmed that the blast disease suppression effect by the ultrasonic treatment was persistent. Moreover, although it was not able to confirm in the test regarding tomato, in the said test regarding rice, the tendency for the seedling height to become slightly small was recognized by ultrasonication. It is known that seedlings become stronger while rolling seedlings with rice while the seedlings become shorter, but it is estimated that the same phenomenon occurs.

<Third Embodiment>
3rd Embodiment demonstrates the onset suppression effect at the time of delaying inoculation of a pathogenic microbe about the rice blast control effect of rice. FIG. 7 is a table showing the verification results of the blast disease control effect by 40 kHz ultrasonic irradiation. Here, the rice cultivar “Aichi Asahi” was irradiated with 40 kHz ultrasonic waves for 2 weeks using the above-described ultrasonic oscillator that outputs the same pulse, and then spontaneously infected in the field (the time of infection is not clear). Seemed to be about two weeks after the end of irradiation). A T test was performed 4 weeks after the end of the treatment. In the case of the untreated group, the number of lesions was 26.2, whereas in the 40 kHz ultrasonic treatment group, the number of lesions was 3.1 and the control value was 88.2. Moreover, in the T test, the probability p of being outside the 95% confidence interval was less than 0.05, and the decrease in the number of lesions was significant, and it was confirmed that it was effective even when infection was slow.

<Fourth Embodiment>
4th Embodiment demonstrates the cabbage wilt yellow disease prevention effect. FIG. 8 is a table showing verification results of cabbage yellowing prevention effect by 40 kHz ultrasonic irradiation. The cabbage cultivar “Four Seasonal Harvest” was irradiated with 40 kHz ultrasonic waves for 2 weeks from 1 week after sowing using the ultrasonic oscillator with the same pulse output as described above, and then the pathogen (Fusarium oxysporum f. ) Spore suspension was irrigated. The test was performed 3 weeks after the inoculation. In the case of the untreated group, the average disease severity was 3.13, but in the 40 kHz ultrasonic treatment group, the average disease severity was 2.93 and the control value was 7.4.

<Fifth Embodiment>
5th Embodiment demonstrates the rice blast control effect by the case where the ultrasonic processing of a different frequency is performed. FIG. 9 is a table showing the verification results of the blast control effect when two types of ultrasonic waves of 21 kHz and 40 kHz are used. Here, the rice cultivar “Aichi Asahi” was irradiated with the above-mentioned two types of ultrasonic waves for 2 weeks using the same ultrasonic output device as described above, and then spontaneously infected in the field (the time of infection was not clear). No, but it seems to be about 2 weeks after the end of irradiation). The test was performed 4 weeks after the end of the treatment. The average disease severity was 1.61 in the untreated zone, the average disease severity was 1.39 (control value 13.7) in the ultrasonic treatment zone of 21 kHz, and the average disease severity was 0.61 (control in the ultrasonic treatment zone of 40 kHz. Value 62.1). Regarding the rice blast control effect, it was confirmed that the ultrasonic treatment at 40 kHz was more effective than the ultrasonic treatment at 21 kHz.

<Sixth Embodiment>
6th Embodiment demonstrates the tomato powdery mildew prevention effect by the case where the ultrasonication of a different frequency is performed. FIG. 10 is a table showing verification results of the tomato powdery mildew prevention effect when three types of ultrasonic waves of 21 kHz, 28 kHz, and 40 kHz are used. Here, tomato variety “Momotaro” is irradiated with the above-mentioned three types of ultrasonic waves for 2 weeks from 1 week after sowing using the ultrasonic oscillating device that outputs the same pulse as described above, and after 1 week after the end of irradiation, infection It was placed in the same meteorological instrument as the stock to promote infection. The test was performed 3 weeks after the end of irradiation. The average disease severity was 1.78 in the untreated group, the average disease severity was 0.83 (control value 53.4) in the 21 kHz ultrasonic treatment group, and the average disease severity 1.00 (control in the 28 kHz ultrasonic treatment group. The average disease severity was 1.17 (control value 34.3) in the ultrasonic treatment section at 40 kHz. Regarding the tomato powdery mildew control effect, 21 kHz sonication was most effective, followed by 28 kHz sonication. Note that the 40 kHz ultrasonic treatment section in this test is relatively less effective than the other treatment sections, but the effect itself is sufficient.

The first to sixth embodiments can be summarized as follows.
(1) A technique for imparting disease resistance by exposing plants to ultrasonic waves, which is a kind of external stress, has been realized. Since the long-term disease prevention effect is maintained by a single treatment, it is possible to grow seedling plants that are resistant to diseases by exposing them to ultrasound during the seedling season, and do not use agricultural chemicals. Or the seedling raising method which reduced use is realizable. It is possible to greatly reduce labor and expenses at the production site.
(2) Since the above technology does not use chemical substances and can impart disease resistance with physical stress, the emergence of resistant bacteria, effects on non-target organisms, residual chemical substances in food, environmental residues -Significant effect that there is no need to consider accumulation.
(3) By using the above technology, it is possible to grow seedlings with high added value for seedling growers. In addition, it is possible for producers engaged in organic farming to effectively control diseases that were difficult to control due to the inability to use pesticides, and it is possible to reduce labor and expand cultivation area.
(4) Disease resistance induced by the above technique lasts for at least several weeks. For this reason, the disease disease prevention effect for a long term is maintained by one process. As a result, it is possible to grow a seedling plant that is resistant to disease by exposing it to the seedling raising period, and it is possible to provide a seedling raising method that does not use or significantly reduces agricultural chemicals.
(5) As a specific example 1 (first embodiment), a technique that can suppress the onset of wilt disease (by Fusarium oysporum f. Sp. Lycopersici), a soil-borne disease, by exposing tomatoes to ultrasound. It was verified that there was.
(6) As a specific example 2 (second embodiment), it can be verified that the technique is capable of suppressing the onset of rice blast disease (by Magnaporthe oryzae), which is an airborne disease, by exposing rice to ultrasound. It was.
(7) It was verified that this technique can suppress disease by exposure to ultrasonic waves even during the growth period.
(8) It was verified that it was possible to grow seedlings resistant to disease by exposure to ultrasound during the seedling stage.
(9) It was verified that the disease resistance was maintained even after planting in this field by exposure to ultrasound during the seedling stage.
(10) It was verified that the exposure of the ultrasonic wave to the plant may be only during the seedling raising period in order to obtain the above-described disease control effect.
(11) It was verified that the longer the period of exposure to ultrasonic waves to plants, the higher the disease-suppressing effect.
(12) It was verified that the disease disease-suppressing effect by exposure to ultrasonic waves on plants lasted for at least 4 weeks after the end of exposure.
(13) It was verified that a plant having a small plant height can be raised by ultrasonic exposure, specifically, that an individual having a small plant height can be raised for rice.
(14) By using a plant activator in combination, it is possible to make the disease onset suppression effect by ultrasonic exposure more effective.
(15) It was verified that even when infection is late, the disease has a certain disease control effect.
(16) It has been verified that there is an ultrasonic frequency effective for disease prevention depending on the pathogenic disease.

The present invention has been described based on the embodiments. This embodiment is an exemplification, and it will be understood by those skilled in the art that various modifications can be made to combinations of the respective components and processes, and such modifications are within the scope of the present invention.

DESCRIPTION OF SYMBOLS 10 Ultrasonic disease control apparatus 20 Ceramic type vibration element 30 Output amplifier apparatus 40 Control part

Claims (15)

1. A cultivation method characterized by irradiating ultrasonic waves to a plant to be cultivated.
2. The cultivation method according to claim 1, wherein the period during which the ultrasonic wave is irradiated is a growth period.
3. The cultivation method according to claim 1, wherein the period of irradiating the ultrasonic waves is a seedling raising period.
4. The cultivation method according to any one of claims 1 to 3, wherein the plant to be cultivated is treated with a plant activator together with the irradiation of the ultrasonic wave.
5. A seedling raising method characterized by irradiating the seedling plant with ultrasonic waves during the seedling raising period before planting in the main field.
6. An ultrasonic disease control apparatus characterized by irradiating ultrasonic waves to a plant to be cultivated.
7. The ultrasonic disease control apparatus according to claim 6, wherein ultrasonic waves having a predetermined frequency are alternately generated at a long pulse interval and a short pulse interval.
8. A disease control method comprising controlling a plant disease using the cultivation method according to any one of claims 1 to 3.
9. A production method comprising producing a plant body or a seedling resistant to disease using the cultivation method according to any one of claims 1 to 3.
10. A disease control method comprising controlling a plant disease using the seedling raising method according to claim 5.
11. A production method comprising producing a plant body or a seedling resistant to disease using the seedling raising method according to claim 5.
12. A disease control method comprising controlling a plant disease using the ultrasonic disease control apparatus according to claim 6 or 7.
13. A production method comprising producing a plant body or a seedling resistant to a disease using the ultrasonic disease control apparatus according to claim 6 or 7.
14. Plant or seedling characterized by being irradiated with ultrasonic waves during the seedling raising period.
15. 15. The plant body or seedling according to claim 14, wherein the ultrasonic wave is generated by alternately generating a predetermined frequency at a long pulse interval and a short pulse interval.

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